*2.6.1 Ophthalmoscopy and Fundus Photography*

Currently, the two most sensitive methods are retinal photography and slit-lamp examination through dilated pupils. Direct ophthalmoscopy by ophthalmologists or trained technicians yields 80% sensitivity and >90% specificity [64]. It is cheap and is considered the method of choice. Fundus photography has the advantage of creating a permanent record, and for that reason, it is the preferred method for retinopathy assessment (**Figures 2**–**4**).

#### **Figure 2.**

*"Background" diabetic retinopathy: few dot hemorrhages (blue arrows) (Dr. Ana Dascalu's private collection, Emergency University Hospital Bucharest, Ophthalmology Department).*

#### **Figure 3.**

*Retinophotography: Severe NPRD: multiple dot and blot hemorrhages, hard exudates, cotton wool spots (blue arrows), macular edema, VB (green arrow) and IRMA (black arrows) (Dr. Daniela Stana's private collection, Emergency University Hospital Bucharest, Ophthalmology Department, PhD thesis).*

#### **Figure 4.**

*Incipient PDR: large ischemic area situated temporally to the macular region, with hard exudates, dots hemorrhages, venous loops, IRMA and intraretinal neovessels; in the mid periphery, pigmented lesions post laser photocoagulation (Dr Ana Dascalu's private collection, Emergency University Hospital Bucharest, Ophthalmology Department).*

### *2.6.2 Fluorescein angiography*

Fluorescein angiography is an invasive, costly, and time-consuming technique but is a sensitive method to detect vascular changes due to rupture of the inner and outer blood retinal barrier in the course of DR [63, 65, 66]. The retinal vasculature is visualized with great accuracy: the examiner may identify tiny microaneurysms and differentiate between microaneurysms (hyperfluorescent) and punctiform hemorrhage (hypofluorescence by masking effect). It is an indispensable

**259**

**Figure 5.**

*Ophthalmology Department).*

*Microvascular Complications of Diabetes Mellitus: Focus on Diabetic Retinopathy (DR)…*

*2.6.3 Optical coherence tomography (OCT) and OCT-angiography (OCT-A)*

exploration before planning different laser treatment, for example to distinguish retinal edema by leakage (which appears white due to dye accumulation) from ischemic retinal edema (which appears as hypofluorescent). In the latter case, the application of laser impacts is not recommended because it leads to exacerbation of

OCT is a completely non-invasive, reproducible and quantifiable. It provides high-resolution images of the retinal layers, choroid, vitreous gel, and the vitreoretinal interface and has become the gold standard for diagnosis, assessment of treatment response, and follow-up up of patients with diabetic macular edema. OCT angiography (OCTA) is a new non-invasive imaging technique that employs motion contrast imaging to high-resolution volumetric blood flow information, rapidly generating images similar to angiographic images [63, 65–67]. It provides a highly detailed view of the retinal vasculature, which allows for accurate delineation of the foveal avascular zone (FAZ) and detection of subtle microvascular abnormalities, including FAZ enlargement, areas of capillary non-perfusion, and intraretinal cystic spaces [66]. The possibility of detecting microvascular changes in diabetic eyes before the presence of visible microaneurysms may have important implications in the future. In this sense, OCTA could be able to quickly

Follow-up of patients with DR involves the ophthalmologist and the diabetologist. Extensive studies in large groups of diabetic patients have shown the beneficial role of strict control of blood glucose, hypertension and dyslipidemia in both

*Fluorescein Angiography: Severe NPRD: numerous microaneurysms (hyperfluorescent dots), areas of nonperfusion (hypofluorescent, blue arrows), venous loops and IRMA, with diffuse leakage (hyperfluorescent, red arrow) (Dr Daniela Stana's private collection, PhD Thesis, Emergency University Hospital Bucharest,* 

*DOI: http://dx.doi.org/10.5772/intechopen.96548*

identify subjects at risk of DM (**Figures 6** and **7**).

retinal ischemia (**Figure 5**).

**2.7 Treatment**

*2.7.1 Primary prevention*

*Microvascular Complications of Diabetes Mellitus: Focus on Diabetic Retinopathy (DR)… DOI: http://dx.doi.org/10.5772/intechopen.96548*

exploration before planning different laser treatment, for example to distinguish retinal edema by leakage (which appears white due to dye accumulation) from ischemic retinal edema (which appears as hypofluorescent). In the latter case, the application of laser impacts is not recommended because it leads to exacerbation of retinal ischemia (**Figure 5**).
